SQLRef

Tutorials and examples for common SQL commands.

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Querying data (DQL)

The Basics

• SELECT
• WHERE
• AND
• HAVING
• LIKE
• BETWEEN
• IN
• NULL
• ORDER BY
• LIMIT
• DISTINCT
• Subqueries

Joins

• INNER JOIN

Aggregations

• AVG
• COUNT
• GROUP BY
• MAX
• MIN
• SUM

Date Functions

• Get Current Date
• Date Trunc

Utilities

• SHOW SCHEMAS

Defining data structures (DDL)

DDL is used to define the structure of data.

Create

• CREATE TABLE
• CREATE INDEX
• CREATE SCHEMA
• CREATE TABLE
• CREATE DATABASE
• CREATE USER
• CREATE VIEW
• CREATE TABLE AS SELECT

Alter

• ADD COLUMN
• Change Column Datatype
• DROP COLUMN
• RENAME COLUMN
• RENAME DATABASE
• RENAME INDEX
• RENAME SCHEMA
• RENAME TABLE
• RENAME USER
• Change User Password
• RENAME VIEW

Drop

• DROP DATABASE
• DROP INDEX
• DROP SCHEMA
• DROP TABLE
• DROP USER
• DROP VIEW

DML

DML is used to alter data.

Insert

• INSERT
• SELECT INTO

Update

• UPDATE

Delete

• DELETE

Sample schema

Most of our examples use the same schema. You can view that schema here